Pipe Grooving Cam Mechanism for Precise Low-Torque Forming

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing roll grooving machines face challenges in accurately producing circumferential grooves in pipe elements with precise tolerances, often resulting in flare and requiring complex designs with significant torque and low production rates, necessitating simpler and faster methods with reduced operator involvement.

Innovation Solution

A device comprising a pinion, carriage, gears, and cam bodies with specific surface profiles and traction surfaces that rotate around the pipe element, allowing for precise groove formation with minimal torque and efficient operation, using a combination of cam surfaces and a die to control groove dimensions and flare.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If roll grooving machines are used to form circumferential grooves in pipe elements, then grooves can be formed with controlled dimensions, but the process requires significant torque, results in low production rates, and causes flare at the pipe end

Engineering Contradiction:
Improvegroove radius toleranceVSAvoidproduction rate
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

Instead of rotating the pipe element as in conventional roll grooving machines, the cam bodies rotate around the stationary pipe element. This inversion eliminates the need to apply significant torque to rotate the pipe, thereby increasing production rate while maintaining groove formation capability through the cam surface profiles

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The cam bodies apply periodic forcing forces to the pipe element as they rotate, with each cam body sequentially engaging the pipe to form the groove. This periodic action allows rapid groove formation without requiring continuous high torque application, thus improving productivity while maintaining precision

Inventive Principle:
Principle #19Periodic action

2Manufacturing precision

If roll grooving machines are used to form circumferential grooves in pipe elements, then grooves can be formed with controlled dimensions, but the process requires complex designs with actuators and operator adjustments

Engineering Contradiction:
Improvegroove radius toleranceVSAvoiddevice complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The cam bodies are designed with self-centering features where the cam surface profiles automatically position themselves relative to the pipe element during rotation. The discontinuities in the cam surfaces engage with the pipe to establish the correct groove radius without requiring operator adjustment, and the cam geometry self-regulates the groove formation process

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The complex actuator systems and adjustment mechanisms found in conventional roll grooving machines are eliminated. The invention extracts only the essential cam bodies with integrated surface profiles and discontinuities, replacing complex mechanical systems with simpler cam-based forcing mechanisms that achieve the same precision

Inventive Principle:
Principle #2Taking out (Extraction)

3Manufacturing precision

If roll grooving machines are used to form circumferential grooves near the end of pipe elements, then grooves can be formed, but the end region of the pipe element expands in diameter causing flare

Engineering Contradiction:
Improvegroove formation accuracyVSAvoidpipe end diameter uniformity
Core Design Contradiction:
Manufacturing precisionVSShape

Solution Approach 1:

The cam bodies are designed with forcing forces that apply preliminary counter-action to prevent flare. The cam surface profiles are configured to distribute the forming forces in a way that counteracts the radial expansion tendency at the pipe end, maintaining diameter uniformity while forming the groove through the controlled application of forcing forces during cam rotation

Inventive Principle:
Principle #9Preliminary anti-action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution enables accurate and rapid formation of circumferential grooves with minimal torque applied to the pipe element, improving production efficiency and reducing operator involvement across various pipe sizes and schedules.

Implementation Method 1

cold working of pipe elements, for example, impressing a circumferential groove in a pipe element

Methodology Applied
Scientific EffectCold working: Cold-forming

Implementation Method 2

Each cam body has a gear which meshes with a pinion to turn all of the cams

Methodology Applied
Scientific EffectMechanical Force: Mechanical Force

Data Source

PatentEP3750644B1Pipe grooving device
Publication Date: 2024.03.13 VICTAULIC
  • EP3750644B1 patent drawingFigure 1
  • EP3750644B1 patent drawingFigure 1A
  • EP3750644B1 patent drawingFigure 2

AI summary

A device for forming a circumferential groove in a pipe element, said device comprising: a pinion fixed against rotation about a pinion axis arranged coaxially with said pinion; a carriage surrounding said pinion, said carriage being rotatable about said pinion axis and defining an opening arranged coaxially with said pinion axis for receiving said pipe element; a plurality of gears mounted on said carriage, each said gear being rotatable relatively to said carriage about a respective gear axis, each said gear engaging with said pinion; a plurality of cam bodies, each said cam body mounted on a respective one of said gears; a plurality of first cam surfaces, each one of said first cam surfaces extending around a respective one of said cam bodies and engageable with said pipe element received within said opening, each one of said first cam surfaces comprising a region of increasing radius, each one of said first cam surfaces comprising a first discontinuity of said first cam surface.